PCB DISTRIBUTION AND ACCUMULATION PATTERNS IN AN ECOSYSTEM WIDE INVESTIGATION OF THE KALAMAZOO RIVER FLOOD PLAIN, MICHIGAN USA

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1 PCB DISTRIBUTION AND ACCUMULATION PATTERNS IN AN ECOSYSTEM WIDE INVESTIGATION OF THE KALAMAZOO RIVER FLOOD PLAIN, MICHIGAN USA P. Bradley, M.J. Zwiernik, P. D. Jones, D. Kay, A. L. Blankenship, K. Strause, and J.P. Giesy National Food Safety and Toxicology Center, Michigan State University, East Lansing, MI 48824, USA; Entrix Inc. East Lansing MI 48864, USA.

2 -From 1957 to 1971 paper mills recycling and processing lead to PCB contamination -Three impoundments were drawn down, Trowbridge was largest (327 acres of former sediment) -Floodplain soils at ~ 10ppm -River sediments at ~ 1ppm -In 1990 the USEPA listed 130 km as a Superfund site, from Morrow dam to Lake Michigan (KRAOC)

3 Location Map Lake Michigan Allegan County Trowbridge (TB) D-Ave Fort Custer (FC) upstream reference area Morrow Lake Dam Kalamazoo County Sampling locations: 325 samples from 4 grids in the Trowbridge (TB) area 215 from 2 grids in the Fort Custer (FC) and other areas Distances between points: FC is ~10 km upstream from Morrow Dam TB is ~40 km downstream from Morrow Dam

4 Chemical analysis only a portion of the studyalso characterized: Populations Reproductive success Habitat suitability Reported elsewhere

5 The Kalamazoo River supports a variety of wildlife What magnitude of exposure?

6 OBJECTIVE To determine if congener patterns change with changes in trophic level, and if so, how? Null hypothesis: Congener patterns do not change relative to trophic level.

7 Preliminary Exposure Pathways Swallows Aquatic emergent insects Bluebirds Terrestrial insects Passerines Aquatic emergent insects Owls Muskrats Vegetation Small Mammals Terrestrial insects Sediments Soils Sediments Soils

8 Preliminary Exposure Pathways Mink Bald Eagle Fish Small mammals Fish & Waterfowl Turtles Muskrats Benthic insects Vegetation Insects & plants Benthic insects Sediments Soils Sediments

9 Mink Aquatic Predator Diet = Fish, Crayfish, Small Mammals Sampling: Trapping Diet determined by examination of stomach contents Tissue analyzed: liver

10 Great Horned Owl Top Terrestrial Predator Diet = Voles, Mice, Songbirds Sampling: Constructed nest platforms Examined pellets + prey remains Sampled eggs, plasma

11 Bald Eagle Top Aquatic predator Diet = Fish, waterfowl, muskrat Sampling: Natural nests Prey remains + observations Reference sites in upper Michigan Sampled eggs (addled), plasma

12 Passerines Terrestrial or aquatic predator House Wren, Tree Swallow, Bluebird Diet = Insects Sampling: Constructed nest boxes Collected eggs, nestlings, adults Examined bolus to determine diet

13 Sample Type Soil + Sediment Plants Worms - depurate + fresh Terrestrial Insects Aquatic Invertebrates - Benthic + Emergent Fish Small Mammals + Shrew Songbirds: (HW, BB TS) Adults, Eggs, Nestlings Muskrat - Liver Mink - Liver Owl Eggs, Tissue Fort Custer Eagle Eggs, Tissue 5 Number: Trowbridge

14 DATA SET 540 samples 63 variables (PCB congener concentrations) 34,000 data points Key questions addressed: How can we evaluate this data? Can we obtain information useful in making decisions? What sort of data analysis approaches make sense?

15 ANALYTICAL METHODOLOGY Mechanical homogenization Soxhlet extraction Sulfuric acid hydrolysis Silica gel column clean up Congener specific analysis by GC/ECD Some variable congener co-elutions

16 TROPHIC LEVELS Aquatic Mink, Eagle 5 Songbird 4 Fish 2,3,4 Muskrat 3 Insect 3 Plant 2 Sediment 1 Terrestrial Owl 5 Shrew 4 Songbird 4 Small Mammal 3 Insect 3 Worm 3 Plant 2 Soil 1

17 AQUATIC ECOSYSTEM TOTAL PCB (ng/g w/w) Trophic Level LOCATION Fort Custer Trowbridge

18 TERRESTRIAL ECOSYSTEM TOTAL PCB (ng/g w/w) Trophic Level LOCATION Fort Custer Trowbridge

19 INTRA-SITE ECOSYSTEM COMPARISON FORT CUSTER TROWBRIDGE Trophic Level TOTAL PCB (ng/g w/w) Ecosystem Aquatic Trophic Level 10 1 Terrestrial

20 INTRA-SITE ECOSYSTEM COMPARISON FORT CUSTER TROWBRIDGE Ecosystem Trophic Level TOTAL PCB (ng/g w/w) Aquatic - unfilled Trophic Level 10 1 Terrestrial - filled

21 Conclusions (Total PCBs) As expected total PCB concentrations are greater at higher trophic levels. Need to define trophic levels carefully based on diet (e.g. small mammals Vs. shrews). Decrease in PCB concentration between soil/sediment and plants due to bioavailability and limited uptake.

22 Congener Patterns - confounding factors Patterns vary by: Locations Trophic level Species Tissues Life stage (adult, egg, nestling) Congener Coelution Is congener pattern analysis helpful?

23 25 20 Bluebird egg Short-Tailed Shrew Grass Earthworm (depurated) Soil 20,33,53 84,90, , , , , ,178, , , ,171, , , Percent of Total PCBs 5, , , , , , ,77 82,

24 Principal Components Analysis Why? Better utilization of all data variability Provides means of visually evaluating data aiding in interpretation Identify differences between trophic levels and between locations How? SYSTAT 10 Standardize data (congener mean = 0; std. dev. = 1) Covariance matrix Varimax rotation (minimizes spread of a congener across PCs) Constrain to 3 PCs for ease of interpretation.

25 Rotated Loading Matrix ( VARIMAX, Gamma = ) C126_129_ C C C C141_ C C C135_ C C156_171_ C C C159_ C128_167_ C C82_ C C C195_ C137_ C C77_85_110_ C C C138_ C133_ C C105_132_ C56_92_84_ C C C C C C C16_ C C C C20_33_ C37_41_ C C28_ C C C C C15_ C5_ C C66_95_ C47_ C C C C81_87_ C C C C C4_ C C Percent of Total Variance Explained PC Variance PC 1 Congener #: 126,129,178,177,174,207,81,135,144,169,156,171,202,201, 194,159,187,128,167,185,183,82,151,107,83,195,208,137,176,209, 77,85,110,120,97,206,138,158 PC 2 Congener #: 22,16,32,45,18,44,20,33,53,37,41, 42,40 28,31,26,27,25,52,15,17 PC 3 Congener #: 47,75,99,119

26 Aquatic + Terrestrial Trowbridge TROPHIC LEVEL 1 Soil, Sediment 2 Plant 3 Muskrat, Invertebrate, Insect Ecosystem Aquatic Terrestrial PC 2 PC 3 4 Shrew, Songbird 5 Eagle, Owl, Mink

27 Aquatic TROPHIC LEVEL 1 Sediment 2 Plant 3 Muskrat, Invertebrate, Insect 4 Shrew, Songbird Fort Custer Trowbridge 5 Eagle, Mink PC 2 PC 3

28 Terrestrial TROPHIC LEVEL 1 Soil 2 Plant 3 Muskrat, Invertebrate, Insect 4 Shrew, Songbird Fort Custer Trowbridge 5 Owl PC 2 PC 3

29 Conclusions (PCA) PCA reduces data complexity and aids data presentation. Assists in evaluating congener profiles within a data set. At lower trophic levels congener profiles are consistent and soil/sediment related. At higher trophic levels congener profiles are more variable and less related to soil/sediment.

30 Questions???????

31 Acknowledgments MSU Museum, Kalamazoo Nature Center, MSU s Aquatic Toxicology Laboratory, John Newsted, Katie Coady

32 Thank You Patrick Bradley 218C NFSTC Michigan State University East Lansing, Michigan 48824, USA Tel: (517) Fax: (517)